The syllable is a prime unit of spoken language from cradle to grave, but its status in the current theory of language production or speaking is quite problematic. There is no consensus on the fundamental question of whether syllables are represented in word memory. In addition, the role played by syllables appears to vary widely across the world's languages. The aim of this project is to provide a multi-pronged attack on this significant weakness in a core aspect of our understanding of language production. The approach includes coordinated experimentation at sites in Taiwan, Spain, and the United States to provide comparable evidence for English, Spanish, and Mandarin Chinese, and computer modelling of the learning and use of syllables. Although the answer to the syllable puzzle is unlikely to be uniform across languages, this project seeks to identify general principles that transcend the particular story for each language. Addressing the status of the syllable in language production theory is critical because of the syllable's central role in making speech possible. Theories, computational models, and therapeutic interventions that misconstrue the syllable are in a very real sense "unable to speak". The project will clarify the prospect for a language general model of word production that encompasses variation in the roles syllables play, and will also specify language specific process models for three of the world's major languages. The latter proposals will provide the kind of specificity needed in computational models of speech production, in speech synthesis software, and in therapeutic interventions including aphasia rehabilitation and speech therapy. Relevance to Public Health: The syllable is a familiar unit of language but its role in the dynamic process of speaking is not well understood. A deeper knowledge of this aspect of the language repertoire is crucial to understanding both developmental and acquired language disorders and to their most effective treatment.